Fire: the need for testing regimes with real-world clarity

The terrible events that took place at Grenfell Tower on 14 June 2017 have rightly prompted a period of reflection across the construction industry. A wide-ranging review of the regulatory framework is underway. Dame Judith Hackitt’s interim report on Building Regulations and Fire Safety, released in December, has criticised a system that is “not fit for purpose” and sweeping changes are expected following the publication of the final report this spring.

We should not wait, however, for this next stage of the process. The interim Hackitt report itself acknowledges that there is no reason why the industry cannot voluntarily adopt cultural changes now ahead of the review’s final recommendations.

A more sophisticated understanding of building fires must inform the entire design and construction process

We must continue delivering the homes that the country needs, and while the full causes of the Grenfell Tower fire are not yet known, there are some basic principles of fire safety best practice that we should follow now to ensure that the buildings we create are safe and provide quality of life for their users.

The interim Hackitt report calls for a shift in culture across the construction supply chain away from doing things cheaply and passing on risk and responsibility to others. This change of mindset must start at the beginning of the specification process – with designers and materials manufacturers. Crucially we need to adopt more real-world testing of materials and their fire performance in systems. Where this is not practically possible, realistic test data and a scientific understanding of fire should form the bedrock of engineered judgments and assessments.

No incident is ever the same, dependent on the cause of the fire, the fire load, the building in question and its design. This makes the job of specifying fire protection systems especially challenging

The science behind compartment and structural fires is complex. No incident is ever the same, dependent on the cause of the fire, the fire load, the building in question and its design. This makes the job of specifying fire protection systems especially challenging. However, testing processes that more closely mirror real-world conditions can help us to better anticipate how systems will perform in a live environment.

The key question is how materials interact. Current regulations tend to deal with individual products, but fire is influenced by the performance and interaction of building systems as a whole. How is the fire performance of a timber structure affected when it is abutted to a concrete frame construction? There will be various design details to consider, the relationship between walls and ceilings, as well as the positioning of load-bearing elements.

Material providers need to create testing regimes that study the performance of products working together but also how their behaviour will change over a building’s lifetime. The partition system in a modern apartment will rarely mirror standard formats. It will be penetrated by plug sockets, telephone wires or television cables, potentially altering the way the overall system performs.

It is hard to model for all eventualities but, at the very least, where full-scale system testing is not viable an appreciation of the complexity of building fires and system performance is vital. We need to share such data and ensure that specifiers can make informed decisions.

There will be legislative changes to come but it remains to be seen whether these will instill a new approach to material performance testing. A more sophisticated understanding of building fires must inform the entire design and construction process. It’s time to move beyond assumptions and adopt testing regimes which are transparent and accessible. Building design and safety should always be informed by credible data reflecting real-world conditions.